In 2013, South Texas singer Jesus "Chuy" Quintanilla was found shot in the head near Mission, Texas. Quintanilla was well known for his ballads, including some about the exploits of Mexican drug cartels.

Elijah Wald, author of the book, "Narcocorrido: A Journey into the Music of Drugs, Guns and Guerrillas," noted previous victims have included singers of a number of genres, not only narcocorridos. Getting entangled with the girlfriend of a criminal, for example, could be dangerous.

"In that world, it's probably more dangerous to be singing romantic songs than narcocorridos because it increases the chances that somebody's girlfriend will suddenly decide that you're the cutest thing ever," he said.

Wald said he didn't have any information on the motive in the Torbellino's killing, but noted that the singer appears only recently to have become successful.

"It's often just a matter of somebody sponsoring someone who isn't paying them back or isn't being properly respectful once they make it," Wald.

"You're in a world where's it's very, very easy to be in the wrong place at the wrong time, or have the wrong friends or look sideway at the wrong girl. The list of things you can do wrong once you're in that world gets very large."